Azo dyestuff and cellulose derivatives dyed therewith



Patented Decl 18, 1928.

teases;

UNITED STATES WINFRID HEN-TRICK, OF WIESDORF, NEAR COLOGNE-ON-THE BHINE, GERMANY, AS-

SIGNOR TO GRASSELLI DYESTUFF CORPORATION, OF NEW YORK, N. Y., A GORPORA- TION OF DELAWARE.

AZO DYEST'UIF AND CELLULOSE DERIVATIVES DYED THEREWITH No Drawing. Application filed February 4, 1927, Serial No. 166,013, and in Germany Februar'yQB, 1926. I

- It has been found that new water-soluble direct monoazo dyes for cellulose derivatives such as acidyl cellulose, cellulose esters, cellulose ethers and their transformation products may be obtained by coupling diazo compounds of dinitroaminophenols or their derivatives with unsulfonated andnon-carboxylated aminonaphthols in the presence of mineral acid bindin agents. The dyes soobtained dye brownis -red, brown, and violet to black colors which are characterized by their remarkable fastness properties, especially their fastness to washing and wetting. It is of especial importance that now for the first time by the use of these dyes, acetate silk may be dyed deep black colors directly by means of water-soluble dyestuffs from a neutral or slightly acid bath. By diazotizing and developing the dyes upon the fibers the dyed colors are deepened and the fastness roperties, especially the overcolor and light astness properties, are improved.

Example 1.

The diazo-compound obtained by diazotizing 199 parts b weight of 4.6-dinitro-2- tminoJ-hydroxy enzol after being separated by filtering under suction and stirred into a small quantity of water is mixed with a' g neutral water solution of 195 parts by weight of the hydrochloride of 1-amino-8-hydroxynaphthalene at 0 C; and then a water solution of about 1000 parts by weight of calcined sodium carbonate is gradually added While maintaining the mixture well cooled and agitated. The formation of the dyestuif takes place quickl When the couplin is complete the dyestu is filtered ofi', washed, pressed and dried. The product is readily soluble in 40 water and dyes acetate silk directly from a neutral or slightly acid batha dee black color of good fastnessto wetting an wash ing. By diazotizing the dyestufi upon the fibers and developing with 2.4-tolylenediamine dyeings of a beautiful deep black color having excellent washing, wetting, overcolor and light fastness pro erties are obtained. Developing with ct yl- Q-naphthyIamine gives violet black dyeings having similar v fastness properties.

By substituting l-amino-G-hydroxynaphthalene for the 1-amino-8-hydroxynaphthalene of the foregoing example one may obtain a readily soluble dyestufi which dyesacetate silk a violet tinged brown color having the same fastness properties. By diazotizing-and developing with phenol or 2-na-phthol-3-carboxylic acid dyeings of a deep violet-brown color having good washing, wetting and overcolor fastness properties-are obtained. The use of Q-amino-S-hydrox naphthalene gives a water-soluble glossy brownish violet dyestufl? which penetrates acetate silk well. The dyestufi when diazotized and developed on the fiber with resorcinol ives a reddish brown and with 2.4-tolylened1amine or 2-naphthol-3-carboxylic acid or phenol or phenylmethylpyrazolone a beautiful redbrown color. All of the dyestufis referred to possess good. washing, wetting and overcolor fastness properties. The replacement of 2-amin0-8-hydroxynaphthalene b 1- amino-5-hydroxynaphthalene gives a direct dye for acetate silk of a black-brown color having a violet tint. The same dyestufi diazotized and developed on the fiber wlth 2-sodium naphtholate or 2.4,-toluylenediaminc or phenol or2-naphthol-3-carboxylic acid V or phenylmethyl pyrazolone gives dee brown colors, and with resorcinol beautifu black-brown colors. These colors also exhibit the above mentioned fastness properties.

The dyestuil' produced in accordance with the foregoing example by coupling diazo- 'tized 4.6-d1nitro-2-amino-l-hydroxybenzol with 1-amino-8-hydroxynaphthalenehas most probably the formula:

NO! By reduction the dyestufi' gives 2.4.6-triamino-l-hydroxybenzol and an amino-1.8- aminonaphthoh The formula of the dyestufl deposited upon the fiber by developing with QA-toluylenediamine most probably is:

Ewample 2.

The diazo-c'ompound 'of 213 parts by weight of partially reduced 2.4.6-trinitr0-1- hydroxy-3-methylbenzol (a mixture of 4.6-

dinitro 2 amino 3 methyl-lhydroxybenzol and 2.4-dinitro-6-amino-3-methyl-1-hydr0xy-' benzol methylpicraminic acid) is mixed with a neutral solutlon of 195 parts by weight of the hydrochloride of 1-amino-7-hydroxynaphthalene. A sodium acetate solution is then added gradually with agitation and cooling until the reaction mixture no longer turns Congo paper blue. After the. coupling is completed the reaction mixture is made alkaline with sodium carbonate andcompounds having most probably the formulae:

and

011(7) N 0 N=N-CmH Both compounds, upon reduction, give the same products, i. e., 2.4.6-triamino-3-methyll-hydroxybenzol and an amino-1.7-aminonaphthol.

The dye deposited upon the fiber by development With 2-sodium naphtholate probably has the formula:

and

The dyes are all dark powders readily soluble in warm water. I claim:

1. As a new product (1 estufis substantially identical with dyestu s obtainable by coupling the diazo compound of a dinitroaminophenol with an unsulfonated and non-carboxylated aminonaphthol in the presence of an acid binding agent, said'dyestufis bein in dry powdered form dark powders rea ily soluble in warm'water, capable of directly dyeing acetate silk a fast color from a neutral or slightly acid bath and having the probable general formula: 7

wherein the benzene ring may contain an alkyl group.

2. Asa new product, a dyestufi substantially identical with a dyestufi obtainable by i coupling the diazo-compound of 4.6-dinitro 2-amin0-1-hydr0xybenzol with l-amino-S- 5 the formula:

hydroxynaphthalene having most probably 3. As a new product, a cellulose derivative dyed with a dyestufl' of claim 1.

4. As a new product, a cellulose derivative dyed with a dyestufi substantially identical with the dyestufi obtainable by coupling the diazo-compound of 4.6-dinitro-2-am1no-1- In testimony whereof, I aifix my signature.

WINFBID HENTRICH. 

